RWModel Class Reference

Implements the "Model" leg of a Model-View-Controller architecture. More...

#include <rw/model.h>

Public Member Functions
	RWModel ()
	RWModel (const RWModel &m)
	RWModel (RWModel &&m)
void	addDependent (RWModelClient *m)
virtual void	changed (void *d=0)
const RWOrdered *	dependents () const
RWModel &	operator= (const RWModel &m)
RWModel &	operator= (RWModel &&m)
void	removeDependent (RWModelClient *m)
void	swap (RWModel &m)

Detailed Description

This abstract base class has been designed to implement the "Model" leg of a Model-View-Controller architecture. A companion class, RWModelClient, supplies the "View" leg.

It maintains a list of dependent RWModelClient objects. When member function changed(void*) is called, the list of dependents is traversed, calling RWModelClient::updateFrom(RWModel*, void*) for each one, with itself as the first argument. Subclasses of RWModelClient should be prepared to accept such a call.

Synopsis

#include <rw/model.h>
(abstract base class)

Persistence

None

Example

#include <rw/model.h>
#include <iostream>
 
class Dial : public RWModelClient {
  int dialNumber;
 
 public:
  explicit Dial(int dialNumber);
  virtual void updateFrom(RWModel* m, void* d);
};
 
class Thermostat : public RWModel {
  double setting;
 
 public:
  Thermostat(Dial* d) {
    addDependent(d);
    setting = 0;
  }
  double temperature() const { return setting; }
  void setTemperature(double t) {
    setting = t;
    changed();
  }
};
 
void Dial::updateFrom(RWModel* m, void*) {
  Thermostat* t = (Thermostat*)m;
  double temp = t->temperature();
 
  // Redraw graphic.
  std::cout << "Dial #" << dialNumber << " says " << temp << std::endl;
}
 
Dial::Dial(int num) : dialNumber(num) {}
 
int main() {
  Dial one(1);
  Dial two(2);
 
  Thermostat therm(&one);
 
  therm.setTemperature(77);
  therm.setTemperature(-4);
  therm.addDependent(&two);
  therm.setTemperature(47);
  return 0;
}

Program output:

Dial #1 says 77
Dial #1 says -4
Dial #1 says 47
Dial #2 says 47

Constructor & Destructor Documentation

RWModel() [1/3]

RWModel::RWModel

(

)

Sets up the internal ordered list of dependents when called by the specializing class.

RWModel() [2/3]

RWModel::RWModel

(

const RWModel &

m

)

Copy constructor. The constructed instance gets a copy of the dependents list from m.

RWModel() [3/3]

RWModel::RWModel

(

RWModel &&

m

)

Move constructor. The constructed instance takes ownership of the dependents list owned by m.

Condition:

This method is available only on platforms with rvalue reference support.

Member Function Documentation

addDependent()

void RWModel::addDependent

(

RWModelClient *

m

)

Adds the object pointed to by m to the list of dependents of self.

changed()

virtual void RWModel::changed ( void * d = 0 )

virtual

Traverse the internal list of dependents, calling member function RWModelClient::updateFrom(RWModel*, void*) for each one, with self as the first argument and d as the second argument.

dependents()

const RWOrdered * RWModel::dependents ( ) const

inline

Allows a peek at the dependent list.

operator=() [1/2]

RWModel & RWModel::operator=

(

const RWModel &

m

)

Assignment operator. Self gets a copy of the dependents list from m.

operator=() [2/2]

RWModel & RWModel::operator=

(

RWModel &&

m

)

Move assignment. Self takes ownership of the dependents list owned by m.

Condition:

This method is available only on platforms with rvalue reference support.

removeDependent()

void RWModel::removeDependent

(

RWModelClient *

m

)

Removes the object pointed to by m from the list of dependents of self.

swap()

void RWModel::swap

(

RWModel &

m

)

Swaps the list of dependents in self with that of m.